GG231 Lecture Notes - Lecture 3: Stratovolcano, Plate Tectonics, Pineapple
Document Summary
Volcanic activity is related to plate tectonics. Mid ocean ridges and subduction zones are where magma reaches the surface and erupts as lava. Craters: depressions at the top that form by explosion or collapse of the summit area calderas: circular/oval depressions that form during explosive ejection of magma and subsequent collapse of a volcano. Volcanic vents: openings through which lava and pyroclastic debris erupt natural processes. Lava and pyroclastic flows weather overtime into very productive soils, favouring crops such as sugar cane and pineapple which lures farmers to settle on slopes putting them at risk. Attracts many tourists to admire the spectacle, banff national parks hot springs. Highest risk in activity in canada is in the mountainous regions of the pacific northwest and central british colombia. Volcanic hazards: lava flows, mostcommon, three types basalt. Rhyolite: slow and people/animals can move out of the way, fish are affected. Elongated, interconnected flow tubes that are elliptical or circular in cross-section -
